Datapath / Capture240p

Capturing 240p signals can be confusing for first time users using the VisionRGB line of framegrabbers. The card and software allow for a much finer control of the incoming video signal which can allow for razor sharp captures. The resulting image is not very appealing if you do not have the video signal optimally timed for pixel perfect capture. The following is a brief guide on how to achieve razor sharp capture. Two main methods to setup the input will be shown. Each method has a different main use case.

Direct Resolution Method

For our example we will be using the direct resolution method. This is where you directly tell VisionWindow all the video signal parameters. This method is ideal if you plan on capturing progressive video sources and want to record in a software that can window capture losslessly such as Open Broadcast Software.

We will be using a Nintendo Wii with the 240p Test Suite in this example. By default this is what VisionWindow will show when we open it attempting to capture the signal.

The screenshot has already had it's colourspace changed. As you can see Vision detected a nonstandard resolution of 336x252 and by default has the window size be 640x480. The capture format is also set to 5:6:5 and scaling is set to fast. Now we know do to various resources including Classic Console Upscaler Wiki , that the wii always has a width of 720px. In this application it also has a height of 240px. We also know the wii follows the Rec.601 video standard reaffirming the 720px width. In this case we now know the hsize is 858. We will now input those settings directly into the relevant portions of VisionWindow. Be sure to hit "Cancel" and then "No". There is a bug in VisionWindow where it will actually just reset the settings to default if you hit "OK" hence this work around.

As you can see we have set both the window size, the input, and the crop resolutions to 720x240 to match our video signal. Exclude Borders have been checked so it is accurately sized. 8:8:8 capture format and Slow (High Quality) scaling have been selected. The Horizontal Size has been adjusted to the correct value of 858. At times the vertical position cannot be adjusted anymore which is why we are cropping on the input tab. The final adjustment is to determine the phase. Depending on your equipment and cabling phase can be a different number for different people. Even changing out things in your own setup can potentially lead to needed to readjust the phase. The Easiest method is to use the Checkerboard Pattern in the 240p Test Suite to find the optimal phasing of the video signal.

To do this we are going to scale our window capture 6 times in OBS via Point Scaling. Conveniently this also partially sets up the optimal way to capture the footage in OBS.

On your canvas you should be able to make out very clear pixels. An in phase optimally timed signal should have razor sharp edges and no bleeding into adjacent pixels as you can see here. The second image is an example of an incorrect phase.

Now that our video is dialed in the next step is processing the video signal for recording in larger resolutions than the source video signal which is explained in ProcessingVideoCapture?

Crop Method

This method is preferred if you plan on using the device in a DirectShow environment. This is ideal if you plan on recording in a software such as Amarec or are dealing with an interlaced video source and would like to deinterlace it with the method of your choosing. While the process is mainly the same there are differences. Keep the DirectShow quirks in mind. What vision detects as the resolution is what you will need to have in your software of choice. This means you cannot capture Wii 240p signals pixel perfect. Therefore in this example we will be moving onto a Super Nintendo. Again we are also going to be using the 240p Test Suite for ease of use.

Again the auto detected parameters does not match our video signal. Since this is a SNES we know that is most circumstances the video signal is 256x240 or 256x224. You can tell if a game has a height of 224 since there will be letterboxing on the screen. In this case the 240p Test Suite by default is 224 height so we will use 256x224 going forward. Again make sure to press "Cancel" and "No" as to not lose the parameters you just input.

You may already notice the differences between now and the prior example. We adjusted the window size, put in the correct Horizontal Size, but kept the input resolution the same and instead put the proper resolution into the crop area. We will also adjust for a correct phase since it is very much incorrect and can be seen without even zooming in on the image. In this case I again scaled to 6x via Point Scaling in OBS.

Now so long we keep this VisionWindow open so as to keep our settings on a console reset, any software such as OBS or Amarec will have the correct settings so long you make it have the same resolution as the input. In this case since Vision detected 320x250 we have to make sure that the software of our choosing also has that as the resolution. Reminder that the cropping in Vision only applies if you are window capturing. You will have to crop the empty space out but using this method you have a lot more options and flexibility in how you can process your video capture since you are no longer limited by just programs that can capture a window.